Breaker-point dresser



Patented July 17, 1934 Y 7 crime? stutter, satellite at; its;

iii.

o: a'tion February 7,

scitmi's." (oust--21? Thisinvention relates. to'a lbreaker-pbintzdress;er; and its principal object .is vtoprovide a simple and convenient toolfor the purpose of accurate;

; lyaand expeditiouslydressing the breaker-points of; electricaldevices, such as autoniobiledistribu: tor heads; and more, particularly,breaker points of the type. carried on a bracket projecting from a;pivoted breaker-point, arm where the arm is offset from; and extendsalong" one side of, the breakerepoint. t Breaker-points are subject toelectrical arcing, these surfaces, howevergnay bev perfectly restored,by ,re g rinding them; true and square.

. The; device org-the present-inventio consists of a: h lding port n,pre e bly; i te a wi h" an overhanging guide portion, andjproiec inaatsub: stantially right angles therefrom, thus, together forminganslz-shap'edelement. The holding portion is adapted to temporarily carryan offset breaker-point arm in such a position that the working face ofthe breaker-point, fast in the bracket, may be brought into contact withthe grinding surface of a Whetstone, without inter- 1 ference from theoffset arm.

The features of this invention for which the protection of LettersPatent of the United States is desired, are collectively grouped in theclaims concluding this specification.

In the drawing,

Fig. 1 represents a plan of my improved breaker-point dresser as it isheld in the hand of a person using it, ready for grinding-abreaker-point;

Fig. 2, a front elevation;

Fig. 3,'a side elevation;

Fig. 4, a plan, showing the dresser with a breaker-point arm in placefor grinding on a Whetstone, parts being broken away for clarity; and

Fig. 5, a fragmentary portion of Fig. 2, showing a certain part in analternate position.

Referring to the drawing, the numeral 10 indicates the dressing toolproper, which consists of a substantially L-shaped structure, one leg ofwhich forms a holding portion 12 and the other leg a guide portion 14.The guide portionis preferably integral with the holding portion andnaturally projects therefrom at substantially a right angle, thusoverhanging the holding portion on one side. The inside face 15 of theguide portion forms a grinding-guide plane, adapted to ride lightly onthe grinding surface 16 of a Whetstone 17. If de-' sired, the face 15may be hardened by any well known means.

The outside face 18 of the holding portion forms an arm-guiding planeand is so disposed that a breaker-point arm 19 can be broughtthereagainst teiiiiibiriiirfiidiii as .riiiqiibi bil -.1216 whereby thearm 19 has angular motion in plane 18 m i 5.. all; I; L1. .1 'H' Aspring 21. pr fe a l ade oifiatsWeL-may ,6 hfiihflQUP-JQQQQLZ'tbeuppennc ti -he dres nato. and; di c edtaha eits free mbttueb eaer-wmt atp teel e may have a limit 20. The tool is now held in one hand,and brought down upon the surface of the Whetstone until the lowerright-hand edge of the guide member 14 touches the stone, and at thesame time, the tool is forced down until the guide 2:1 plane coincideswith the grinding plane.

At 34 is indicated in dotted lines, a breakerpoint arm of anotherdesign,that is, where the breaker-point 38 is on the opposite side of thebracket 35 from that of the offset-arm, 36, instead of on the same sideof the offset-arm 37, as is the case with breaker-point arm 19.

In the use of the tool, the operating effect upon the breaker-points inboth the cases just described, is of course the same, since the position of 33 and 35 is common to both. 99

The portion 25 is provided as a convenience for holding straightbreaker-points, such asthose indicated at 26 and 27. These straightbreakerpoints may be of different kinds, and may been; disposed innotches 28 and 29 respectively, by means of a flat spring 30, whichlatter may be. suitably tensioned under a knurled nut 31, threaded on astud 32, to clamp the breaker-points- Since breaker-point arms are oftenmade left and right, in the same equipment, it will be noted in Figs. 2and 5, that the slot 24 and hole 20-1 are in duplicate, but on oppositesides of the tool, so as to accommodate either right-hand or lefthandbreaker-point arms. For this purpose, the spring 21 is lightly held ineither of the slots 24, as the case may be, whereby the spring may beeasily interchanged between left and right positions whenever required.Other holes (not shown) may be provided for pivoting arms of otherdesigns, as desired. 1

w Theslotted portions may have any suitable positions but are preferablylocated at, or in proximity to, the ends of the line of intersectionbetween the grinding-guide plane and the armguiding plane.

While a specific embodiment of this invention is herein shown anddescribed, it should be clearly understood that various changes in thedetails thereof, can easily be made without departing from the spiritand scope of the following claims. 7

Having fully described my invention, what I claim is:

1. A breaker-point dresser, including in combination, an L-shapedstructure having a surface on the inside of one leg thereof adapted toride on a grinding surface, the other leg of the L having a guidesurface on the outside thereof, thus constituting a holder disposedtrans versely to the first-mentioned surface, and means for mounting abreaker-point arm on said holding' member guide surface in such a mannerthat the face of the breaker-point carried by said breaker-point arm maybe brought into coincidence with said grinding surface.

2. A breaker-point dresser, including in com bination, an L-shapedstructure, the inside of one leg of which constitutes a guide memberhaving a surface adapted to ride on a grinding surface, while the otherleg of the L constitutes a holder disposed transversely to the guidememher for the purpose of supporting a breakerpoint arm, and a springoperative to normally depress said breaker-point arm to a position belowsaid guide-member riding surface.

3. A dresser for breaker-points fast in an arm structure, including incombination, a substantially L-shaped element having an arm-guidingplane on the outer face of one leg of said element and a grinding-guideplane on the inner face of the other leg of said element substantiallyat right angles to said arm-guiding plane; means for holding abreaker-point arm with the side face thereof in coincidence with saidarmguiding plane, and means for causing the working face of thebreaker-point carried by said arm, to bear against a grinding surface inthe said grinding-guide plane.

4. A dresser for breaker-points fast in an arm structure, including incombination, a substantially L-shaped element having an arm-guidingplane on the outer face of one leg of said element, and a grinding-guideplane on the inner face of the other leg of said element, said planesbeing disposed at suitable angles relative to each other, means forpivoting a breaker-point arm so as to be movable in the arm-grindingplane, and a spring extending'from a point in proximity to the line ofintersection between the said planes to a point where said spring exertsa pressure operative to cause the breaker-point to bear on 'a grindingsurface in the said grinding-guide plane.

5. A dresser for breaker-points fast in an arm structure, including incombination, a substantially L-shaped element having an arm-guidingplane onthe outside face of one of its legs and a grinding-guide planeon the inside face of its other leg disposed at a suitable angle to saidarmguiding plane; means for pivotally securing a breaker-point offsetarm in said arm-guiding plane, a spring mounting near each end of theline of intersection between the arm-guiding plane and thegrinding-guide plane, and a spring adapted to be interchangeablypositioned in either of a said spring mountings.

CHARLES J. STOCKER.

